SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '818180169d07edb27e14144949ea7244b558894f5749f2f3f95388ca0b2848d9' 
  AND token = 'SbTs205bTMisrDQkhgzROHSLSSekxffe9iwa1KjHY2g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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