SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '266b0bcf396843cbf1f0bc666587ceaa8849a460dbba5bd5bc218c55ddd717dd' 
  AND token = 'g2hWLvlalhdW3SADDxOcc2ei4VQ0ghuItbQ3he/tPN8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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