SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2e7d071f407d42c9b4cc9cbc852c10f58b35e8475e8746fd304d698885aca7f' 
  AND token = 'fRlJjTVgcZW/9FmxCBaw56XkzZ+GQhe9AIoDQcogbNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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