SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02eb4eddcf0ae477d8e8e8bdff8d5fa595ff91f60bffee80eb586e3a4d9d0d5d' 
  AND token = 'wdihkySPPeuMBx94eKSprVxEjrhh7ZDH6Z0kVN5V16w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}