SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05a8bc9e2839261eb7b3491cffbef25874d55c88046b1af557e4c5f27db158af' 
  AND token = 'MVhYu3WljwTb8LyHGhWMVjAMnJMomaLFlH7K41UsaRk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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