SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '626c8310ed47b0b489a9eb970b49c9187bf71c9e838f2d354f7ddf8e043bbdd0' 
  AND token = 'y8Ye5thgmWJjfWLiOBaYk0U2vgok2AYPlLJJmeI7A1k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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