SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9c79d93376aae8ea486802d87533a239105a19633524430bc61950438150109' 
  AND token = 'khSncBIateCroTZLE3GHLtlvbi2+8qeaxU0H2pQgiFU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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