SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfbaa4d1e757b60bcdff95e4edbed0feab3e05e5f517dce140cc956487ba5674' 
  AND token = 'mT4vw9MlYxqtZcjsd76O8Aq3R1tnzE1+dV9Lxy85HJI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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