SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ceef41093a964c55bed105c1d7ca2d145fe31585844caa848d73f834f4dcf58' 
  AND token = '7xEBSk+Vzw/ufdS01QSZElaWXyefHojBl8e9DDp+VI8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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