SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da69fda2562feef99c253ef36787a858c8c32d13cc4b5a660fb792a871b7ea01' 
  AND token = 'scOulxV/rSplgWP6GDSzPQpIiA3g5o+QjFNH4ogFUds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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