SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0bbf57c97fa8fa84952b950ddb37bc3977170f9c7877aeae260662e56f2b51b5' 
  AND token = 'viRsSV04qtKZohRSKAkfYDu6cpzx2tZnCMPC3LPANRc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}