SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8b67b9a38e9ea0542f7a62b1f27f39bcd7fb8e9114e3e54e7816f344fc3fa472' 
  AND token = 'AmpFr479oVM5W8IEZIzFxs74xtdJs2uQrPfSHbPrCnc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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