SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e97f8a636c83355c8d467ffc322f0af8c2900d79f89491951720c6eaac677fe7' 
  AND token = 'EQw4ojoT2CwnoqXyc9LVIx4MASs0XbaIMbut46PtULo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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