SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '73b504ae302af60993d4d7bb4a9551c86e3c57ba10caea9d2ca2b12bd1030960' 
  AND token = 'R0aimQBELaqVR6HCzjlZY+fhA8uoTHqivbxQ/aG0ZYk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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