SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abf946ce3e74e72ce5ee6a7364a7de65c89967287148e6678f4f1739dca5dd22' 
  AND token = 'ENXsBJddSTQDpnktYdqUg5Jb07MSnC+L0+Y/Q9Q77Ys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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