SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1dbd1d737dffacdf7779036c6e9b6c8e9e6142aba3e13a20d17e3ccd545848eb' 
  AND token = 'NQ6+QVSb8j+5QrYLH1lXRX/JUP8XZSp/D3BnzCEvPgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00063

JSON explain

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