SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b23cd33a75664b1aec7249ac57c332ef784547eb47524883f17a32370225d8e' 
  AND token = 'Vghz41OdcK/5jqD70AlygSyWKfSFRL+nSm7om3Ld57w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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