SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd1d53eb69fd390a920be56c55902affc622ea0fe123b5568b6709014dab91a9' 
  AND token = 'gPYwF2AXlxz/prBJVN5RrmfxqNJ6rm89zqxLJI9zb6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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