SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '317f836144100f2972a0199856c57a130b59f7454cbcbab67dec0e6cd9937b45' 
  AND token = 'dxwzmGjbe31JJ++upyvcGCt3ucYAhUnujUlIosNHX3s=' 
  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"
    }
  }
}