SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '63a81c6cb5121417d84b8678f7a363ffd5d34824b160650a3e2d7d14c328d691' 
  AND token = 'p/p5F5q1EoYkvARzVw2QrChXk3ht89ipcmaWrjgf2u4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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