SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be0290c1da3f9c2a5f8cb357a47b31e0913f5caffc88a2d631bb4285553763b4' 
  AND token = '7Aw7s2PA3qF+mXJWj9Bkeg85J5mMfY/vXlgLTWsTPNU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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