SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a1f291c15e9b843ab4597f8149c8bf94311434ec02ca943f55ffff7c7407b33' 
  AND token = 'jGreeCsTQplscPWOh7dgQCKvkgnQQwYw7OO+FAEGViQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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