SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b22c27f75a6fc6899a2e1964ed2d376fbfe286f9468050cd8ed1506e4b014d2' 
  AND token = 'gsvt/yMx3zYixFDmUwZdKG28BX4MB9pcB3Gnnw8hSoE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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