SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0ca46409ac766118dc9b32ecfc4f9622237f4a2c807690ced68d464139d43c8' 
  AND token = 'YKLP4W+cMDpZmgwXJZsZwjRxKzprxwsh2g9nAn+Hf84=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}