SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7dd66660e964145ffb2622efd9f271a7cbd8dc9a62d0655535a7f58cd82ece65' 
  AND token = 'S7bg2FZMrrcfHYqdjYJcnDKLFBWWA/QbuVzcmVCXyYw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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