SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ff381867162ee78eb3a211e35d4d357ea3e962ce6d29f5f622b4467a69c79f2' 
  AND token = 'hsAaYS0hSxfid/026rVmT4h9sHHtu6mmXdmvUEnhaQk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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