SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1457ce19de96e60de4cddfa4021e678e6483d62d191b7674092d6c9a481ef20' 
  AND token = 'w9UazbL0s6xGgvtElszsybz07PrBAxRwlCG2qv+p0so=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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