SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0c741810d03e1931f3e7a446d2e62cb2995eebacd552136de87e262b049d130' 
  AND token = 'OtHOkwcyxhThWDJs0y36l6X4UaTZqNjPI/ZgvhJO1Bo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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