SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '974b666e1baf9c2704119386a0ea60a66f13795cf48ed136d2e53ef732749120' 
  AND token = 'WvJM7TMbHu/IKZXetcPqs+V8Fpu2lDFy22qYJCZ0fhw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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