SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f92182af02af87a4294a9518efb177eb4e8506588907588494bbd43286627ff' 
  AND token = 'cOmR0JE/zKPgjtVAuXcO/H+k9MWvrzzTc6aGlgRxCEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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