SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e505d15931cc507850595219fbea879def25f9d9c0567ed69801c13e6ff6399' 
  AND token = 'xZEHgva/amOkiz/da21MbDfIDusSPrsx6Or82h59kPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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