SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90cbac375b9325e4e58a6c8db20a7a0c1e23b596ed1552802ac82eaa9aebba61' 
  AND token = 'XvkeeFLm5+738YsxVL6RbgcjmdNynyxWf1Crf07Rog0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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