SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3736a4938e042f9a8dd3b0f3bf121446897e424d96674044ec005cd4d5a4b935' 
  AND token = 'o/4vimC9rV3HsIf59r0q1c2OpZDfABNW95ePfhuiY4U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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