SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31ca67551a5426260d1fbdefbff4e95dafe952c86fd15cc77a231e83e2410384' 
  AND token = 'wfVsbZFnBYCnbUeEAYDsZ9XqRpVWzHVWiqBEkhLrxdk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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