SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3167269a9aac2a46f02f98da422c26f882b79d409326963cfc1dbe39dd70a626' 
  AND token = 'Ql5seym3dLmM858ypWWORRXlsQbJIpb/xSxzPM1DsvA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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