SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af2313850068d238fbf027344548a43d165bb77b94855f146a96f7cb15d66e50' 
  AND token = 'OG3VYN6SvOZmkCfyX8x0SjwfEOXqLiLP1sx4rFzIo9Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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