SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60dfa36078deab3884603d90f6226131462fb3bf2887fb4027301bf881e3fd53' 
  AND token = 'I2/jRj9eb8qFUKWeaJYfPBZIozzCuqlt5n9CVU0E8+w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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