SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '997015f3a107bae2a8a7ca247e593fd0d26db436ed0b7260845db16bb09772da' 
  AND token = 'h0m0jKKjoEggSMjavBX9ZUX8AGTJMrV72jowk/LRQ4M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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