SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '813c54d5b1f97a9843cff098f2f0c61d8c45e5a4897a887eb85fdc3eca70a2a4' 
  AND token = 'zcx7Nl2dK2HBhjSm4+ZC42U/hFgexdBSLJruQlFOhwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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