SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'efbbd95fb1c46a86368d3891e6d81b2e34ac9c910063cfb1519a7c63110eccdd' 
  AND token = 'foKpoIUMtVhe5fkDtAimhVnFKn1jjtv25fuhVLZNSEQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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