SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f6717b29d9887704fadee850c8a26f063e0ecf1078ad5bde0e4517c7169d8907' 
  AND token = 'PEHWUd8QN3gAjsLiySvOQhwAAqPZwpAr8thUNIdYFuU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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