SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '949329477e91b94eb6b83389dcaacbc3631931ba5298d483e1d00b5f0186c61d' 
  AND token = 'bEdA/Wici4Pl74bdvZA+WkEso0GRmJi3rUUPKJ/3kcE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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