SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2000e07a25b621f7847a952078187d1ae22de5c68dfc7fc098228641bfd1792f' 
  AND token = '+Odlzn7DhZfuGpW75z+27VEDiZmnST4nQEPb7NW2QvM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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