SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1150b013e6da36aed6b31dca8521ead437ebf54d116e44ea1f41063febc04d39' 
  AND token = 'KW13d+1+xQZoXZ1uTTGzn+BxqHSlUl7XKwY3uBQwmR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}