SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8928113dfe56102ab30cdf6ebd422ded495b1531b529a7b2f8164c2ca14d5c61' 
  AND token = 'FQ79N2gwUvdEXhYWhXTFqF/XtTQjtuYMzb1Bx3RgzkQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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