SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef9fa698d64b15d436fa7fbfe7d28411c1b6e95ee7ffbe84088d54aedfd37904' 
  AND token = 'ufCHlG626SmdlmxCXeSbun+23uYIYF+eQ/7qFWKzcUA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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