SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32c7ef57b4a962fc7bd5f0d32956936d725339ad6725638a7114458a49daeaae' 
  AND token = 'v9rGybE9YZIUQi/AIttitINXDB+sEXTGhbG03D+pGBQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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