SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fbfbac1a40090f4646f867a2f34b3be78c0230326575c1c8bad2469ad355d3ca' 
  AND token = 'KBx8fq7319qMiJp4onHu5OyqGvYbovgRaq4raf6zjOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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