SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8200d653f14bb13b64ef8990f527d6e0e5028e68b326f6da7950b4fb90786176' 
  AND token = 'zTdKWzzUkbayzqohlXmq3eqcNEi8Y8dmTshl/IZoieA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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