SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9861f0673cb0a2a86d779468b61bc5b236ce9e7c342774506315dfc2934b3d69' 
  AND token = '8JO8sNggM+w072A3QFVz9TNmmuwS38Hfm8NFLE3FzOo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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