SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14a86e19ff63fc2894e01900f0638bdb2114bfdbb4d77980d56747632e11e152' 
  AND token = 'eHSPauQY2WagThdfi5NgRokqul/8eBReoByFMgITlnA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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