SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92ceebe318dba1056aefcbc9e705c0caceff0be45f3ebd6c8ff3c5df5f0a9d92' 
  AND token = 'GsNpVdLK4i6cBOE9rSkS1dzq2hYwI/9p0zMsBrxkggI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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