SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5036e94906f5c2254a4e47ca6ccb6a01bcf5bf15e65882757a835d88da91b093' 
  AND token = 'FgrQw+rsgujn8B0iEp7t+XKGiJl/kx7zHlnMYvhzSgo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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