SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '29e92544a0bbf663402e8f2fdbe307fc53eb707ebc6c247cfe917b010bab45fa' 
  AND token = 'thIkYcuIFoMCnYMFtYUdxNn+iCCE/aZalPQmP13IL7s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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