SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0aa33b2daa01368838dc343247a30d18f4af376a465055f63cc48177e8316eb7' 
  AND token = 'eOmSpGT6LGnHaKkBSHUzVS6SB/XMaFCehiOQQeyuJBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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