SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1cc2a263cd9768fa6c78c924d2c3ed4c493f49e10ace839a7c10453da1c94dd8' 
  AND token = 'NNOflDCetMtwpgCTHYDZLfwlD/9NCRHk4ZiqEzRNn6M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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