SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60331e8de59f03259b80ef31b858e4bf18336cc470349bc154676ac374d3b4b8' 
  AND token = 'MfKRaPAZsDQtoN9uWzxzyAZchVl6G1XyTWtUnB4lR/A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00057

JSON explain

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