SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f950e46011714a86b794904f5f8fb83c5bbd6612795ea8e7aa93585385ccc0ac' 
  AND token = '4wSZ/+AcWDJfNkHR7M/vZ5NKLnp+Qh1Qh0F0qiqeGjc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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