SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e7f4f260996670aaabd5916bf881a4b69119a41248b050be307b13333ef79ea' 
  AND token = 'ev31rtRdYKjtd6gKTE8sBjZJ9QDbks/ZoGayPW5GWVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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