SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b226fa0544103e7cc54e95109d783d9179bed8958741926a3132d1cddbde0ae' 
  AND token = 'nXuJjr8ujGR0cYFtVthyZChX24sYbQCM+TwhRm3DDaM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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