SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd8c25a1ac120dbabdcd8b5d844f163d85fa4c12f645542ac9385b5740a56bab' 
  AND token = 'QWG8Ma6vijYZhlzWB3y6POszqf7zTlvA36g9m/QLqJ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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