Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'a19910ae2d25cb747c26a7bd0f4b5687d1f2432c030766c1526d3c666ee28bdb' 
  AND token = 'HmhQbPFBnheTC5Kf4bOfzyyfHjT2ZnIVwYaOKuPoSs0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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