SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3480a86b34ad6ffb9c78ca0aa343304717e23f07f271a414099fbcc3caf2b9bd' 
  AND token = 'Y651Qq6lvTCvsgu1vJlRcz3r4Ggs3ZfWWR2ofxIrLgg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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