SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '204fc5d766f226d67fa224a2015cc452dd2ffa0117bfa8d640a3408593dba344' 
  AND token = 'MSLhJgVHTtuI3LTVPZERUv/X93UZ5so1JovjSQRh/qA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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