SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1585ed1d0534d87957e3f62a541e28ab6394ab2f005727b48be2b6634be71009' 
  AND token = 'vGhKYNP/PBq+CM5Z2wroOOuAGkh1dRFNzSUtn4TimSE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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