SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1341b16246141b4365867b7fe1112700de75f9ebe66afae853af04aea9430591' 
  AND token = 'VqhsuqEWZc6MpZ7wnK6X7GYmtvk3YqgY9NPVQLxitGE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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