SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0aaad547a948010793cafb0d64fe748d077f170369a5b17c7e26d90fef09b458' 
  AND token = 'X+NRPTroIINvReTHYbsG8UtfFRXAmadx0Su/swidyEQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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